Pulse and Digital Circuits Mid - I, February - 2011

1.What is the response of step input to a high pass RC circuit
  • V e-t/RC
  • V (1- et/RC)
  • V et/RC
  • V(1- e-t/RC )
Answer: A
2.A comparator is a basic building block in a system used to analyze the -------- distribution of noise generated in active device
  • Both frequency and phase
  • Amplitude
  • Phase
  • Frequency
Answer: B
3.Common base configurations is little used because
  • High voltage gain
  • High current gain
  • It has low input impedance
  • High input impedance
Answer: C
4.The Vce (sat) of Si n-p-n transistor at 27 c is
  • 0.7 v
  • 0.3 v
  • 0.8 v
  • 0.1 v
Answer: B
5.Monostable multivibrators generates
  • Pulse wave form
  • Ramp signal
  • Sine wave
  • Square wave
Answer: B
7.The reverse saturation current increases approximately for every ------- rise in temperature
  • 30 c
  • 50 c
  • 70 c
  • 10 c
Answer: D
8.Zener diode has ---------- temperature coefficient
  • some times positive and sometimes negative
  • Only negative
  • Both positive and negative
  • Only positive
Answer: B
9.Turn off time of the transistor is = -------
  • toff =tf +ts
  • toff =tf +ton
  • toff =tfd +ts
  • toff =ton +ts
Answer: A
10.What is the name of the circuit which converts square wave in to spikes
  • Low pass RC
  • Bi stable multi
  • High pass RC
  • Monoshot
Answer: C
11.For DC input signal capacitor C acts as a ___________
Answer: Open ckt
12.The average value of the output value of an RC high pass circuit is _________
Answer: zero
13.In RC integrator circuit the output is taken across --------
Answer: capacitor
14.The clamping theorem is given by --------
Answer: Af/Ar=Rf/R
15.No of quasi stable states of astable is----------
Answer: 2
16.The percentage tilt in the response of a square wave input to a RC differentiator circuit is given by
Answer: (T/2RC) X 100
17.The current flowing through the capacitor when the voltage across the capacitor is V __________
Answer: C (dV/dt)
18.The expression of pulse width for monostable multivibrator is ____________
Answer: T=0.69RC
19.When the diode is forward biased it acts as ____________
Answer: closed switch
20.The out put voltage Vo of RC differentiator for input Vi is ____________
Answer: (RC) dVi/dt